Ashley Mansfield is a bricklayer in the UK.
How would you characterise your current work?
I am a bricklayer working for myself and also subcontracting to larger firms.
How do you feel about mathematics?
I have always felt apprehensive about maths. When I was younger I felt the focus on mental arithmetic as a way of judging me on my ability was pretty high-stakes (especially from my father) – this made me feel a little inadequate, and I still feel weak at mental arithmetic. Even though I now know that maths is more than just working out numbers quickly, it’s hard to get away from that. A lot of the maths I use daily is the same because bricks and blocks are standard size – so memorising things like the 75 and 225 times tables over time has helped me feel less apprehensive. (In the UK, the usual size of a modern brick is 215 × 102.5 × 65 mm, which adds to a 10 mm mortar joint to make approximately 225 × 112.5 × 75 mm.)
Image credit: John C Bullas, (Flikr) under Creative Commons
Different 'standard' house brick sizes by country (source: Wikipedia)
What is it about your work that is mathematical?
My work relies heavily on maths. I use it every single day, measuring cuts of materials, setting out the positions and heights of walls from architectural drawings. I am always considering angles, measurements, dimensions and space as part of my job.
How do you use maths, calculation or numeracy practically in your work? What tools do you use to help you?
I use ratios of sand and cement in the mortar to make it the right strength. Typically above ground I would use a 6:1 mix of sand and cement; we would start with knowing a 25kg bag of cement contains 4 full shovels therefore needing 24 shovels of sand for a good mix. You get quite good at judging the shovelfuls accurately! Some stronger mixes below ground need more cement and the addition of extra lime i.e. 3:2:1 sand, lime and cement. I mainly use a tape measure and a calculator in terms of tools to help me with maths.
Do you think maths is creative? If so, how?
I do think maths is creative; a lot of what I build gets its beauty from maths. The building must be able to support itself, and the way architects and engineers solve the problems whilst making the structure remain attractive to the eye is in itself a very creative process.
Do you use or rely on any maths that you learnt in school?
I would say that day to day I use all the 'basic' maths that I was taught in school, but one I thought I would never use but do is Pythagoras’ Theorem to find right angles. I would use a 3:4:5 triangle to find a right angle or I would use lengths of wood cut and nailed to this to make a set square. It’s never millimetre perfect but it’s accurate enough for what I would need – and I guess estimating and knowing how accurate I need things to be is another skill I use from school.
How would you change the school curriculum, if you had the chance? Why?
I think I would suggest pupils got to experience using maths in a working environment more – maths is a physical thing to me in my working day, not abstract or just on paper. I got to do field trips for other subjects but I don't recall any for maths: maybe seeing and using the formulas and ideas in real life would help guard against the feeling that they would never be used again after school. That’s certainly not my experience!